Conor Friedersdorf posted an article in today's online Atlantic with the title
The Most Dangerous Myth: That Liberals Are Peaceniks. The short reply to this is "Duh!" However, I felt compelled to write a longer answer as follows. Naturally I can only speak for myself but I've had a few people congratulate me for providing a succinct description of liberal attitudes toward war.
Of course we aren't [peaceniks], and never have been. I object to unnecessary wars and wars of adventure. I object to war by proxy and the use of force before all diplomatic venues have been exhausted.
I agree with the necessity of war for common defense and honoring our treaties. I agree with the use of military force to intervene when we're invited to do so. I agree with joining in a military coalition where there's broad support to stop attempts at genocide or similar crimes against humanity.
I do not agree with invading a country because we're greedy for their resources or because we wish to install a government that's friendly to us. I do not agree with war as an immediate option; I think it should always be the option of last resort. Carry the big stick, fine, but be cautious with its use. Don't insist on a stick bigger than you need to get the job done.